The coronavirus appears to have spread undetected in the U.S. for about six weeks, according to an analysis by researchers in Washington state.
The Centers for Disease Control and Prevention announced the first confirmed case of coronavirus in Washington on Jan. 20. A second case was confirmed Friday.
Researchers who examined the genomes of both infections said the second case likely descended from the first, The New York Times reported. The individuals in the two cases did not have any known contact. The second case occurred weeks after the first, suggesting it spread through other individuals in the area.
The first patient, a man in his 30s who returned from Wuhan, China, the epicenter of the outbreak, recovered after being treated at a hospital. The second patient, a teenager with no known travel exposure, was able to recover at home.
"This strongly suggests that there has been cryptic transmission in Washington State for the past 6 weeks," Trevor Bedford, an associate professor at the the University of Washington, tweeted. "I believe we're facing an already substantial outbreak in Washington State that was not detected until now due to narrow case definition requiring direct travel to China."
Bedford told The Times that only two of 59 sample sequences from China had the genetic variation found in both cases. Scientists have analyzed more than 125 genomes from samples around the world.
If true, as many as 1,500 people may have been infected over a period of weeks, lead researcher Dr. Mike Famulare of the Institute for Disease Modeling, told The Times. Famulare said the most likely number was between 300 and 500 cases who "have either been infected and recovered or currently are infected now."
Other researchers and state officials told The Times they had little reason to doubt the findings.
Officials in Washington announced Monday that 18 people in the state have tested positive for the coronavirus, five of which have died. Officials announced a possible outbreak Saturday at a long-term residential care facility, where more than 50 people have reported symptoms associated with the virus. Gov. Jay Inslee declared a state of emergency over the weekend.
Federal officials have confirmed 87 cases around the country, including in California, Florida, New York, Oregon and Rhode Island. Globally, there have been nearly 90,000 confirmed cases of the coronavirus and 3,000 deaths.
"Unfortunately, we are starting to find more COVID-19 cases here in Washington that appear to be acquired locally here in Washington," Washington state health officer Dr. Kathy Lofy said Monday. "We now know that the virus is actively spreading in some communities."
The number of cases in the U.S. is expected to increase "dramatically" after the CDC expanded its testing guidelines, The Washington Post reported. The CDC previously limited the criteria for who should be tested for the virus, and most tests had to be sent to a lab in Atlanta after the agency sent faulty tests to state labs. The CDC focused on individuals who traveled to China or had contact with someone who did until the weekend.
"Once we start testing more broadly this week, we are almost certain to learn that there has been community transmission for a while in many places," Andy Pavia, who heads the Division of Pediatric Infectious Diseases at the University of Utah health system, told The Post.
The CDC denied that it had turned down any requests for tests outside of the previous criteria, but patients who sought tests said they were unable to get them.
A 56-year-old Maryland woman who returned from Italy, one of the countries hit hardest by the virus, told The Post that she was unable to get a test at the hospital despite suffering from flu-like symptoms. She imposed a self-quarantine to be safe.
"It's almost impossible to get a damn test," she said. "I could have been passing this all over D.C."
A 30-year-old man who returned from Japan last week said he did not meet the criteria for the test despite being checked into a hospital with a 102-degree fever and cough. He also self-quarantined in his apartment. The man wrote on Reddit that he "wanted people to realize that there are probably more people like me."
"At no point am I saying, 'I have coronavirus.' I'm just saying I have symptoms that are like it, and no one is testing me," he added.
Vice President Mike Pence, who was charged with overseeing the Trump administration's response to the virus despite a history of ignoring science and enabling the worst HIV outbreak in state history as the governor of Indiana, insisted that the administration's moves made the country safer.
"I think it's all a reflection of the fact that early on in this crisis, in January, the president took the unprecedented step of suspending all travel from China and establishing a quarantining effect," he told CNN.
Trump also said he was "very strongly" considering closing the southern border with Mexico, leading to allegations that he was using coronavirus "as an excuse to pursue his nativist agenda" and an "excuse to peddle racism and xenophobia." Experts have said that border closures are "ineffective" to prevent the spread of the virus.
Former Vice President Joe Biden, who appeared on CNN right after Pence, slammed the administration's response.
"We knew this was coming back as far as January," he said. "They didn't even begin to prepare the testing kits. This is something that's elementary."
The Trump administration has also come under fire for trying to downplay the threat posed by the virus even as Dr. Anthony Fauci, the director of the NIH's National Institute of Allergy and Infectious Diseases, appeared in several television interviews to warn that the "beginning of community spread" was "really quite concerning."
"I'm concerned that you're going to see a lot more cases. I mean, certainly when you have a number of cases that you've identified and they've been in the community for a while, you're going to wind up seeing a lot more cases than you would have predicted," he said, contradicting Surgeon General Jerome Adams' insistence that the risk was "low" and would kill "far" fewer people than the flu.
"My concern is — as the next week, or two or three go by — we're going to see a lot more community-related cases," Fauci told CNN. "And that's of great concern."
Trump has gone so far as to call Democratic criticism of his coronavirus response a "new hoax."
"I'm not talking about what's happening here. I'm talking what they're doing — that's the hoax," the president said at a Saturday press briefing. "That's just a continuation of the hoax, whether it's the impeachment hoax or 'Russia, Russia, Russia' hoax. This is what I'm talking about. Certainly not referring to this. How could anybody refer to this? This is very serious."